Microsoft kicked off the Exchange 2013 buzz with the mid-July release of Exchange 2013 Preview build. Today we take a look at the installation process, requirements and some of the design changes the new release introduces.

Exchange 2013 Preview build does not support coexistence with any of the earlier Exchange releases. However this will change and the final release will coexist with both Exchange 2007 and 2010.

Exchange 2013 requires at least one writable Windows 2008 SP1 Domain Controller and a Windows 2008 Global Catalog server or later. As for the Schema Master this can be Windows 2003 SP2 or later. Windows Server 2003 forest functionality level is required.

Exchange 2013 server roles must be installed on a Windows 2008 R2 or Windows 2012 member server. As usual it is recommended not to install Exchange 2013 Preview on an AD server. However this is exactly what I did to generate the screenshots. You will see this flagged at the 'Readiness Check' step later. The management tools may also be run on Window 7 SP1 and Windows 8 Preview.

The minimum Windows Outlook version is 2007 SP3. Also supported are Entourage 2008 for Mac (Web Services Edition) and Outlook for Mac 2011. So this is going to be the end of the line for Outlook 2003.

Indeed Exchange 2013 is changing client connectivity significantly. RPC over TCP is no longer supported. Instead Exchange 2013 only supports RPC connectivity over HTTPS. This should allow Outlook to more easily switch between on-premise and cloud servers. On the other hand this will require changes in some Exchange add-ons Microsoft Partners are providing today.

Before Installing

As usual Microsoft is making available a very detailed article for satisfying all the installation prerequisites. So the first step will be that of following this article to the letter: Exchange 2013 Prerequisites

Clearing all the prerequisites will take some time. Do this on the side as it may easily take most of the day. With the prerequisites out of the way we are ready to start the actual installation.

The biggest change that pops out at installation time is the change in server roles. Exchange 2007/2010 provided many distinct roles that could be distributed over different servers. We had the Edge Transport, Hub Transport, Mailbox, Client Access and Unified Messaging roles. Exchange 2013 merged these roles into two, the Mailbox and Client Access roles.

The Exchange 2013 Client Access is the one handling client connections and also acts as a Front End Transport service. It takes care to route client requests to the correct Mailbox server. It also delivers emails to/from the internet and performs filtering such as Connection, Sender, Recipient and Protocol Filtering.

Connections to the Client Access server are stateless so clients can reach Exchange through different Client Access servers transparently.

The Mailbox Server is the one doing all the work. Once a connection is established, it provides storage, searching functionality, high availability, unified messaging and more.

Exchange 2013 Preview does not provide a dedicated Edge server role. I did not find any official statement on whether an Edge server will be included in the final release. However a comment from Bharat Suneja (MSFT) hints that this void is going to be filled:

"...Exchange Server 2013 doesn't yet have an Edge transport server role, but you can continue to use Exchange 2010 Edge servers until we deliver an Edge transport server role in a future release..."

Native Edge support allowed Exchange 2007/2010 to better integrate the perimeter server with the Exchange Organization. EdgeSync and the ability to configure the Edge using the Exchange Management Shell/Console helped in providing this integration. Using non-integrated alternatives is a step backwards, but then again this is only a preview release.